PROJECT SUMMARY FOR ADMINISTRATIVE SUPPLEMENT These supplemental funds will be used to further characterize and stage the Tg-FDD mouse model of Cerebral Amyloid Angiopathy (CAA). In the parent award, we proposed a series of biochemical and pathological approaches to characterize the mechanistic connection between vascular amyloidosis and neuroinflammation. Recently the Stark Neurosciences Research Institute (SNRI) and Indiana University School of Medicine (IUSM) have agreed to purchase an nCounter barcoding technology system and a Digital Spatial Profiling (DSP) system platform developed by NanoString Technologies. DSP is based on the nCounter barcoding technology that enables spatially resolved, digital characterization of proteins or mRNA in a highly multiplexed (up to 800-plex) assay. This technology is unique not only in the state of Indiana, but in the entire Midwest. To enhance our understanding on the contribution of AD-related risk factors to glial activation and neuroinflammation associated to vascular amyloid deposition, in this supplement, we propose to measure gene expression levels in our CAA mouse model (Tg-FDD mice) utilizing Neuroinflammation and AD-related risk factor panels from nCounter NanoString. We will also map the location of specific neuroinflammatory responses in relation to vascular amyloid deposits using the DSP platform. We will utilize the NanoString panels to examine the expression of the set of hundreds of immune-related genes in Tg-FDD mice brain lysate before the appearance of amyloid vascular pathology, at early stages of vascular amyloid deposition, and at late stages of vascular pathology. Confirmation of gene expression alterations will be confirmed via a secondary analysis for both RNA and protein levels. From each brain region known to be associated with the accumulation of vascular amyloid, we will examine the expression of immune-related genes utilizing the NanoString Neuropathology panel technology. This will permit us to associate an immune profile with the progression of vascular amyloid pathology throughout the brain. All analyses will be performed in Tg-FDD mice with wild type littermates at three different ages: 6, 12, and 18 months. Mice described in aim 1 in the parent grant will be utilized in this supplement. This technology (https://www.nanostring.com/scientific-content/technology-overview/digital-spatial- profiling-technology) was not included in the parent grant budget since it is a new technology and was not available during the parent grant submission. !